Improvement in millstone-dressing machines



W, B.-CHASE.

MILLSTONE DRESSING-MACHINE.

PatentedmJan.11,1876.

lllllll momma N-PETERS, PNOTO-LITMOGRAPHER. WASHINGTON, D C.

UNITED STATES PATENT OFFICE.

WILLIAM B. CHASE, OF FARIBAULT, MINNESOTA.

IMPROVEMENT IN MILLSTONE-DRESSING MACHINES.

Specification forming part of Letters Patent No. 171,992, dated January 11,1876; application filed November 27, 1875.

To all whom it may concern:

Be it known that I, WILLIAM B. CHASE, of Faribault, Rice county, Minnesota, have invented anew and Improved Millstone-Dressing Machine, of which the following is a specification:

Figure 1 represents a top view, and Fig. 2 a vertical longitudinal section on the line C 0, Fig. 1, of my improved millstone-dressing machine.

Similar letters of reference indicate corresponding parts.- The invention is an improvement in the class of millstone-dressing machines in which a pick or cutting-tool is operated by a vibrating lever, and caused to travel over the face of the stone by means of pawl-and-ratchet mechanism; and the improvement relates to the construction and arrangement of parts, as hereinafter described.

A represents a sliding frame that is supported and guided in suitable manner on a strong base-frame, B. At one end of the sliding frame A is arranged a reel, E, that is revolved by a hand-crank to lift the pick-lever, and give quick and repeated blows to the stone by the pick. The lateral rods of the reel engage the forward-extending arm or rod D of a pickcarrying lever, O, that is clamped to a lateral guide-shaft, 66, which slides and turns readily in bearingsof the sliding frame A. One or more picks are attached by set-screws to the end of the lever U, and adjusted thereby accurately to the depth of dressing required. The extension-rod D of the lever O is fulcrumed to a bolt, [2, at the lowerpart. A lever-handle, D, acts on the upper rear part of fulcrumed rod D for lowering the front end of the. same when depressing the lever, so that the reel may then engage the rod, and, in quick succession, raise and drop the picks. The

spring draws the extensionrod D back as soon as the lever is released, so as to interrupt thereby the blows of the pick.' The sliding frame A is fed forward on the base-frame for dressing off the stone by means of a longitudiso that, by carrying the handle F from one side to the other, the screw is turned, and the sliding frame and pick-lever moved forward there- The degree of the forward motion of the pick is defined byastud, e,ofthelever, which comes in contact with pins 6 of an arc-shaped guide-piece, f, and a removable pin, f, that is set into holes of the guide-pins according as the feed-screw has to be turned more or less for the adjustment of the picks, as shown in Fig. 2. A greater or less degree of forward motion of the pick may thus be produced, and the operation of the same on the stone accurately adjusted, and interrupted by the handle of the picklever, the forward feeding of the pick being obtained by the screw-turning lever pawl-and-ratchet mechanism.

Having thusdescribed my invention, I claim as new and desire to secure by Letters Patent- 1. The combination, with the lever G, carrying the pick, and arranged to vibrate on the shaft a, of the pivoted arm or extension D, fulcrum-rod b, shown and described, to operate as specified.

2. The combination, with the stationary frame B, the pick-lever frame A sliding thereon, and the screw F, arranged as shown, of the ratchet-wheel d, the lever F, carrying pawl 11, and stop-pins for limiting the movement of said lever, as shown and described. .WILLIAM B. CHASE. Witnesses:

FRANK BERRY, GEO. A. ARMSTRONG,

spring I), and lever D, all as 

